Where is the largest coral reef?

The Great Barrier Reef, off the coast of Queensland in northeastern Australia, is the largest coral reef system on Earth. It stretches for more than 2,300 kilometers and covers an area of about 344,000 square kilometers — larger than Italy. Made up of nearly 3,000 individual reefs and 900 islands, it is the biggest structure built by living organisms and is even visible from space. The reef teems with life, including more than 1,500 fish species, 400 types of coral, and marine animals from turtles to whales. Sadly, it faces serious threats from warming seas, which cause coral bleaching.